JP4635570B2 - Method and apparatus for manufacturing organic electroluminescence element - Google Patents

Description

  The present invention relates to an organic electroluminescence element expected to be widely used as a flat panel display used in a portable terminal such as a television, a personal computer monitor, a cellular phone, a surface-emitting light source, illumination, and a light-emitting advertising body. It is.

  Organic electroluminescence elements are expected as flat panel displays that replace cathode ray tubes and liquid crystal displays because of their advantages such as wide viewing angle, fast response speed, and low power consumption.

  An organic electroluminescent element has a structure in which an organic light emitting medium layer is sandwiched between two electrode layers of an anode layer and a cathode layer, and light is emitted from the organic light emitting medium layer when a voltage is applied between the electrode layers and a current flows. A light-emitting display element. Generally, a transparent electrode is used as a material for the anode layer, and light generated in the organic light emitting medium layer is extracted from the transparent anode layer side.

  There are passive matrix driving and active matrix driving as a driving method of a display composed of organic electroluminescence elements, but in order to increase the size and definition of the display, active matrix driving in which each pixel is driven by a switch (TFT) is used. This is advantageous because it can be driven at a low voltage. However, in the conventional device, since light is extracted from the transparent anode layer formed on the TFT substrate, the aperture ratio is limited by the TFT, wiring, etc., and there is a problem that the light extraction efficiency is lowered.

  In recent years, with respect to the problems of such conventional top-emitting devices (top emission devices), devices in which the cathode layer is made into a transparent electrode or devices in which the order of forming the anode layer and the cathode layer on the substrate is reversed. A top-emitting device (top emission device) represented by the above has been devised. In these top-emitting elements, the aperture ratio can be increased as compared with conventional bottom-emitting elements (bottom emission elements), and the light extraction efficiency is improved (see Patent Document 1).

  However, when a metal that has been conventionally used as a cathode layer is used as the material of the cathode layer of the lower surface type light emitting device, it is difficult to achieve both sufficient transmittance and resistivity. Further, when a transparent electrode such as ITO, which has been conventionally used as an anode layer, is used as a material for the cathode layer, there is a problem that the electron injecting property to the organic light emitting medium is impaired. Therefore, after forming a thin film of a low work function metal material excellent in electron injectability, which has been used as a conventional cathode material, within a range that does not interfere with the transmittance, the transmittance and low efficiency conventionally used as an anode layer are formed. By laminating and forming a transparent electrode material such as ITO excellent in the thickness, it was possible to form a cathode layer having sufficient electron injecting property and translucency, and at the same time, having both low resistance.

When the transparent electrode layer such as the ITO film described above is formed, it is generally generated by a film forming method using plasma such as a sputtering method or an ion plating method. There is a problem that the plasma reaches the substrate to be deposited, the organic light emitting medium layer is damaged by the plasma, and the luminous efficiency is lowered.

Japanese Patent Laid-Open No. 2001-43980

  In view of the above problems, an object of the present invention is to provide a transparent electrode film forming apparatus and a manufacturing method that do not damage an organic light emitting medium layer, and to provide an organic electroluminescent element with high luminous efficiency.

The invention according to claim 1 is a method for manufacturing an organic electroluminescent element, in which a second electrode is formed by plasma film formation on a laminated substrate in which at least a first electrode and an organic light emitting medium layer are laminated . A shielding part is provided between the plasma generation part of the plasma film forming apparatus and the laminated substrate, the shielding part has an opening having an inclined opening ratio and has a ground potential, a slit, and a radius that is A movable shielding plate made of a disk larger than the major axis of the laminated substrate, wherein the plasma film forming step comprises forming the film while rotating the movable shielding plate. Is the method.

Invention of Claim 2 is a manufacturing method of the organic electroluminescent element which forms a 2nd electrode by plasma film-forming on the laminated substrate by which the 1st electrode and the organic luminescent medium layer were laminated | stacked at least, A shielding part is provided between the plasma generating part of the plasma film forming apparatus and the laminated substrate, and the shielding part has an opening and a conductor having a ground potential, and the movable having the opening having the same shape as the conductor. In the plasma film forming step, the aperture ratio is changed by sliding the conductor or the movable shield plate, and at the initial stage of film formation, the opening portion of the conductor is covered with the movable shield plate. The organic electro luminescence is characterized in that the opening ratio of the shielding portion is reduced to reduce the opening ratio of the shielding portion, and the opening portion of the conductive member and the opening portion of the movable shielding plate are combined in the latter stage of film formation to increase the opening ratio of the shielding portion. Luminescence element It is a manufacturing method.

A third aspect of the present invention is the method of manufacturing an organic electroluminescence element according to the first or second aspect , wherein the movable shielding portion is made of stainless steel .

According to a fourth aspect of the present invention, there is provided the organic electroluminescence element manufacturing apparatus in which the second electrode is formed by plasma film formation on a laminated substrate in which at least the first electrode and the organic light emitting medium layer are laminated. A plasma film forming apparatus for forming a film includes a target unit, a plasma generating unit, a holding unit for holding a laminated substrate, a shielding unit capable of changing an aperture ratio, an exhaust port, and a gas supply port. The shielding portion includes a conductor having an opening portion with an inclined opening ratio and having a ground potential, and a movable shielding plate having a slit and made of a disk having a radius larger than the major axis of the laminated substrate. The shielding part is provided between the plasma generation part and the holding part of the multilayer substrate, the exhaust port is disposed closer to the target part than the conductor having the opening part, and the gas supply port has the opening part. Is disposed on the substrate side of the electric conductor, a manufacturing apparatus of an organic electroluminescent device characterized by a movable manner in the movable shielding plate is a rotating movement.

According to a fifth aspect of the present invention, there is provided the organic electroluminescence element manufacturing apparatus in which the second electrode is formed by plasma film formation on a laminated substrate in which at least the first electrode and the organic light emitting medium layer are laminated. A plasma film forming apparatus for forming a film includes a target unit, a plasma generating unit, a holding unit for holding a laminated substrate, a shielding unit capable of changing an aperture ratio, an exhaust port, and a gas supply port. The shielding portion includes an electric conductor having an opening and having a ground potential, and the movable shielding plate having an opening having the same shape as the electric conductor, and the shielding portion includes the plasma generating portion and the laminated layer. Provided between the holding portion of the substrate, the exhaust port is disposed closer to the target portion than the conductor having an opening, and the gas supply port is disposed closer to the substrate than the conductor having the opening, OK Is a manufacturing apparatus of an organic electroluminescent device characterized by a movable manner sexual shielding plate is sliding.

A sixth aspect of the present invention is the organic electroluminescence element manufacturing apparatus according to the fourth or fifth aspect , wherein the plasma film forming apparatus is a DC magnetron sputtering apparatus .

The present invention has been made to solve the above problems.
In the method for manufacturing an organic electronics luminescence device according to the present invention, a shielding part is provided between a plasma generation part and a laminated substrate in a plasma film forming apparatus. In the initial stage of film formation, the aperture ratio of the shielding part from the plasma film forming apparatus to the organic light emitting medium layer is reduced to reduce plasma damage to the organic light emitting medium layer, and in this state, the target electrode material is made to a certain thickness. Laminate. Then, since this electrode material layer functions as a protective layer for the organic light emitting medium layer, even if the aperture ratio from the sputtering apparatus to the organic light emitting medium layer is increased thereafter, the organic light emitting medium layer is not damaged and deposited. Speed can be improved.

According to the manufacturing apparatus and the manufacturing method of the present invention, it is possible to reduce the damage caused by the plasma generated from the plasma generation unit of the plasma film forming apparatus to the organic light emitting medium layer. As a result, deterioration of the organic light emitting medium layer can be suppressed, and an organic electroluminescence element with high light emission efficiency can be provided.

In an embodiment of the present invention, in order to provide a manufacturing apparatus and a manufacturing method for reducing damage to an organic electroluminescent element, an organic light emitting medium layer is laminated in a plasma film forming apparatus including at least a plasma generating part and a target part. A shielding part is provided between the laminated substrate and the plasma generation part. The aperture ratio with respect to the laminated substrate in the shielding portion varies from small to large. This effect will be described later.
The structure of the shielding part is not particularly limited as long as the plasma can be shielded and the aperture ratio can be adjusted from small to large, and any structure can be used. It is also possible to install one or a plurality of shielding plates or the like in combination.

  In the organic electroluminescent element manufacturing apparatus and manufacturing method of the present invention, the structure of the shielding part is not particularly limited as long as the plasma can be shielded and the aperture ratio can be adjusted from small to large.

As the best mode of the manufacturing apparatus and manufacturing method of the organic electroluminescence element of the present invention, the shielding part preferably uses a conductor having an opening and a movable shielding plate. Although both can be installed alone or as a shielding part, it is more preferable to combine both in order to enhance the plasma shielding effect. In this case, the order of arrangement of the two is not particularly limited, and either may be installed on the plasma generation unit side.
The conductor having the opening is provided for canceling the electric charge of the plasma particles, and is preferably at the ground potential. The atoms jumping out of the target portion pass through the opening of the conductor having the opening and are deposited on the stacked substrate.
The movable shielding plate is provided to directly shield the plasma particles, and by having mobility, the aperture ratio with respect to the laminated substrate can be adjusted from the plasma generation unit. As an embodiment of the present invention, when the movable shielding plate is a disk and rotates around the center, an opening such as a slit is provided in the movable shielding plate, and atoms that jump out of the target portion at a certain rate Allow to pass.

  Hereinafter, as an example of an apparatus for manufacturing an organic electroluminescence element according to the present invention, a description will be given based on the drawings, but the present invention is not limited to this structure.

As an example of the organic electroluminescence element manufacturing apparatus of the present invention, an example in which DC magnetron sputtering is used in a plasma film forming apparatus is shown in FIG. The plasma film forming apparatus includes a plasma generation unit 5, a laminated substrate holding unit 10 that holds the laminated substrate 2, and a shielding unit 6. The shielding part 6 is located between the plasma generation part 5 and the holding part 10 of the laminated substrate. A target unit 4 and a magnet 9 are provided on the lower surface of the plasma generating unit 5, and the target unit 4 is installed on the upper surface of the magnet 9. Further, a deposition preventing plate 8 is installed.
The shielding portion 6 is composed of a conductor 6a having an opening and a movable shielding plate 6b, and the conductor 6a having an opening is on the plasma generating portion side, and the normally movable shielding plate 6b holds the laminated substrate. Although it is on the part 10 side, an upside down arrangement is also possible. Further, a gas supply port 7 is provided between the conductor 6a having an opening and the laminated substrate holder 10, and a gas exhaust means (not shown) is provided. Even if the laminated substrate 2 is formed while being fixed to the holding unit 10 of the laminated substrate, the laminated substrate 2 is held on the holding unit 10 of the laminated substrate and is formed while being transported in parallel to the laminated substrate surface. Also good.

  As an example of the organic electroluminescent element manufacturing apparatus of the present invention, an example in which counter target sputtering is used in a plasma film forming apparatus is shown in FIG.

  The plasma film forming apparatus of the organic electroluminescent element manufacturing apparatus of the present invention is not limited to the above example, and any transparent electrode film forming apparatus having at least a plasma generating part and a target part can be used. For example, RF magnetron sputtering, electron cyclotron resonance sputtering, ion plating using a pressure gradient plasma gun, or the like can be used. Among these existing plasma film forming methods, it is more preferable to use a counter target sputtering method with less plasma leakage to the laminated substrate and a DC magnetron sputtering method with less plasma leakage and excellent discharge stability. However, the present invention is not limited to this apparatus.

  As a method for installing and transporting the laminated substrate, it is desirable to select the best method according to the form of the substrate. For example, as shown in FIGS. 1 to 4, the surface 11 on the organic light emitting medium layer side is placed or transported toward the lower surface. Alternatively, the substrate may be placed vertically and installed or transported with the organic light emitting medium layer side facing the side. In addition, when the substrate is placed and film formation is performed, fixed film formation or rotation film formation may be performed. Further, when the substrate is transported to form a film, single-wafer transport film formation or roll winding transport film formation may be used.

  The structure of the shielding part 6 is not particularly limited as long as the plasma can be shielded and the aperture ratio can be adjusted from small to large, and any structure can be used. It is also possible to install one or a plurality of shielding plates or the like in combination.

  The conductor 6a having an opening is not particularly limited as long as it is a metal material or alloy material having conductivity so that plasma does not leak to the substrate side, but iron, chromium, aluminum, copper, nickel, tantalum, It is desirable to use metal materials such as tungsten and these alloy materials. The form of the opening may be a mesh or a line as shown in FIGS. 1 and 2, but it is desirable that the opening ratio be as small as possible so that plasma does not fly to the substrate as early as possible. However, if the aperture ratio is reduced, the film formation rate decreases. Therefore, the aperture ratio is reduced only at the initial stage of film formation to form a film without damage (FIG. 1), and the aperture ratio is gradually increased (FIG. 2). The method is more preferred. When the electrodes are laminated to some extent, the laminated second electrode layer functions as a protective layer for the organic light emitting medium layer, so that the aperture ratio of the shielding portion can be increased after the initial stage of film formation. In order to cancel the charge of the charged plasma particles, it is desirable that the electric potential of the conductor having the opening is a ground potential. If necessary, a plurality of electric conductors are stacked, and a predetermined electric potential difference is provided between the electric conductors. It is okay to spend.

  If the gas supply port of the plasma film forming apparatus is arranged between the conductor having the opening and the laminated substrate 2, or the conductor itself having the opening has a structure including the gas supply port, The plasma is scattered and absorbed, and it is less likely to fly to the laminated substrate 2 through the conductor having the opening and cause damage. Furthermore, if the gas exhaust port of the plasma film forming apparatus is arranged closer to the target part than the conductor having the opening, the plasma generated from the plasma generating part by the gas flow will fly to the laminated substrate 2 and cause damage. Less to give.

In addition, a movable shielding plate can be installed in order to block the plasma flying from the plasma generator to the laminated substrate 2. Although the movable shielding plate and the shielding plate having the above-described opening can be installed alone, it is more preferable to combine both in order to enhance the plasma shielding effect.
By making the movable shielding plate a shielding plate having no opening, it can be used as a shutter so that plasma does not fly to the substrate until the plasma discharge is stabilized. As shown in FIGS. 1 and 2, it is possible to prevent the substrate from being exposed to plasma at all times by providing the movable shielding plate 6b with a slit-shaped opening and rotating the movable shielding plate 6b. In these cases, in the initial stage of film formation (FIG. 1), since the plasma is blocked by the movable shielding plate, damage to the organic light emitting medium can be suppressed. In the case where such a disc-shaped movable shielding portion having a slit is provided, it is desirable that the radius of the disc be larger than the major axis of the laminated substrate, and the width of the slit can be set according to the size of the substrate and the film formation conditions. The thickness of the movable shielding plate can be set freely, but if it is too thick, the corners of the slits block the trajectory of the target atoms passing from the oblique direction, so a certain degree of thinness is necessary. In addition, the material of the movable shielding plate can be arbitrarily selected as long as it is a material capable of shielding plasma. For example, stainless steel or the like is desirably used from the viewpoint of strength and ease of handling.
When the shielding by the movable shielding plate 6b is finished at a stage where the laminated substrate is transported and the film formation has progressed to some extent (FIG. 2), the aperture ratio from the target portion increases, and the lamination speed can be increased.
Further, when the second electrode layer is laminated without the laminated substrate being transferred, the opening similar to the conductor 6a in which the movable shielding plate 6b has an opening as shown in FIGS. It is good also as a structure which can switch between the interruption | blocking state (FIG. 3) and an open state (FIG. 4) by operation | movement, such as a slide and rotation. In this case, in the initial stage of film formation, the aperture ratio is set to be small (FIG. 3), plasma damage is suppressed, and then the movable shielding plate 6b or the conductor 6a having the opening is slid to increase the aperture ratio. (FIG. 4).

  Hereinafter, as an example of the organic electroluminescence device according to the present invention, a substrate / first electrode (anode layer) / organic light-emitting medium layer / second electrode (transparent cathode layer) / adhesive layer / substrate is laminated in this order. The case of the material will be described with reference to FIG. 3, but the present invention is not limited to this configuration. The anode and the cathode are reversed, and the substrate / first electrode (cathode layer) / organic light emitting medium layer / It is also possible to laminate in the order of the second electrode (transparent anode layer) / adhesive layer / substrate. Further, both the first electrode and the second electrode may be transparent electrodes.

  Here, in the present embodiment, the materials of the substrates 20a and 20b are, for example, glass, quartz, polypropylene, polyether sulfone, polycarbonate, cycloolefin polymer, polyarylate, polyamide, polymethyl methacrylate, polyethylene terephthalate, polyethylene. Plastic films and sheets such as naphthalate, or metal oxides such as silicon oxide and aluminum oxide, metal fluorides such as aluminum fluoride and magnesium fluoride, metals such as silicon nitride and aluminum nitride Translucent substrates with single or laminated polymer resin films such as nitrides, metal oxynitrides such as silicon oxynitride, acrylic resin, epoxy resin, silicone resin, polyester resin, aluminum or stainless steel Metal foil such as sheet, silicon substrate, non-translucent substrate in which a metal film such as aluminum, copper, nickel, stainless steel, etc. is laminated on the plastic film or sheet can be used, and at least one is translucent Any material can be used as long as it is present.

These substrates may be used as a driving substrate by forming a thin film transistor (TFT) if necessary. As the TFT material, organic TFTs such as polythiophene, polyaniline, copper phthalocyanine, and perylene derivatives may be used, and amorphous silicon or polysilicon TFTs may be used.
In addition, it is more preferable to heat-treat these substrates in advance to reduce the moisture adsorbed inside or on the substrate as much as possible. Furthermore, in order to improve the adhesion of the material laminated on the substrate 20a, it is preferable to perform a surface treatment such as an ultrasonic cleaning treatment, a corona discharge treatment, a plasma treatment, or a UV ozone treatment. These substrates may be provided with a color filter layer, a light scattering layer, a light deflection layer, a flattening layer, or the like as necessary.

First, the first electrode 21 (anode layer) is formed and patterned as necessary (FIG. 5). Here, the material of the anode layer is not particularly limited as long as it does not impair the hole injection property to the organic light emitting medium layer and is a low resistance material, and a transmission type using a transmission film made of a metal oxide or the like. An organic electroluminescence element may be used, or a top-emission organic electroluminescence element may be formed using a non-transmissive film made of a metal material. Materials include metal oxides such as indium oxide and tin oxide, metal complex oxides such as ITO (indium tin complex oxide), indium zinc complex oxide, and zinc aluminum complex oxide, and metals such as gold and platinum. Either a single layer or a laminate of a material, a fine particle dispersion film in which fine particles of these metal oxides or metal materials are dispersed in an epoxy resin or an acrylic resin can be used.
If necessary, a metal material such as copper or aluminum may be provided as an auxiliary electrode in order to reduce the wiring resistance of the anode layer.

  As a method for forming the first electrode, depending on the material and form, dry film forming methods such as resistance heating evaporation method, electron beam evaporation method, reactive evaporation method, ion plating method, sputtering method, gravure printing method, A wet film formation method such as a screen printing method can be used. As a patterning method of the transparent anode layer, an existing patterning method such as a mask vapor deposition method, a photolithography method, a wet etching method, or a dry etching method can be used depending on the material and the film forming method.

Next, the organic light emitting medium layer 22 is formed (FIG. 6). The organic light emitting medium layer 22 in the present invention can be formed of a single layer film or a multilayer film containing a light emitting substance. Examples of the configuration in the case of forming a multilayer film include a hole transport layer, an electron transporting light emitting layer or a hole transporting light emitting layer, a two-layer structure comprising an electron transport layer, a hole transport layer, a light emitting layer, and an electron transport layer. By separating the hole (electron) injection function and the hole (electron) transport function as required, or by inserting a layer that blocks the transport of holes (electrons), etc. Furthermore, multilayers can be formed.
In addition, the configuration and function of the multilayer film of the organic light emitting medium layer 22 do not necessarily need to be divided in this way. For example, a layer having the functions of both a hole transport material and a light emitting material is formed, or one of these multilayer films is formed. It is also possible to form a layer in which materials of part or all layers are mixed.

  Examples of hole transport materials include metal phthalocyanines such as copper phthalocyanine and tetra (t-butyl) copper phthalocyanine and metal-free phthalocyanines, quinacridone compounds, 1,1-bis (4-di-p-tolylaminophenyl) Cyclohexane, N, N′-diphenyl-N, N′-bis (3-methylphenyl) -1,1′-biphenyl-4,4′-diamine, N, N′-di (1-naphthyl) -N, Aromatic amine low molecular hole injection and transport materials such as N′-diphenyl-1,1′-biphenyl-4,4′-diamine, polyaniline, polythiophene, polyvinylcarbazole, poly (3,4-ethylenedioxythiophene) ) And polystyrene sulfonic acid and other polymer hole transport materials, polythiophene oligomer materials, and other existing hole transport materials It is possible to choose from.

  As the light-emitting material, 9,10-diarylanthracene derivatives, pyrene, coronene, perylene, rubrene, 1,1,4,4-tetraphenylbutadiene, tris (8-quinolinolato) aluminum complex, tris (4-methyl-8-) Quinolinolato) aluminum complex, bis (8-quinolinolato) zinc complex, tris (4-methyl-5-trifluoromethyl-8-quinolinolato) aluminum complex, tris (4-methyl-5-cyano-8-quinolinolato) aluminum complex, Bis (2-methyl-5-trifluoromethyl-8-quinolinolato) [4- (4-cyanophenyl) phenolate] aluminum complex, bis (2-methyl-5-cyano-8-quinolinolato) [4- (4- Cyanophenyl) phenolate] aluminum complex, tri (8-quinolinolato) scandium complex, bis [8- (para-tosyl) aminoquinoline] zinc complex and cadmium complex, 1,2,3,4-tetraphenylcyclopentadiene, pentaphenylcyclopentadiene, poly-2,5- Diheptyloxy-para-phenylene vinylene, coumarin phosphor, perylene phosphor, pyran phosphor, anthrone phosphor, porphyrin phosphor, quinacridone phosphor, N, N'-dialkyl-substituted quinacridone phosphor , Naphthalimide-based phosphors, N, N′-diaryl-substituted pyrrolopyrrole-based phosphors, low-molecular light-emitting materials such as phosphorescent phosphors such as Ir complexes, polyfluorene, polyparaphenylene vinylene, polythiophene, polyspiro, etc. Of these low molecular weight materials. Or copolymerized material and can be used other existing luminescent materials.

Examples of the electron transport material include 2- (4-bifinylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole, 2,5-bis (1-naphthyl) -1, 3,4-oxadiazole, oxadiazole derivatives, bis (10-hydroxybenzo [h] quinolinolato) beryllium complexes, triazole compounds, and the like can be used.
The thickness of the organic light emitting medium layer is 1000 nm or less, preferably 50 to 150 nm, even when formed by a single layer or a stacked layer. In particular, the hole transport material of the polymer organic electroluminescence element has a large effect of covering the surface protrusions of the substrate and the anode layer, and it is more preferable to form a film having a thickness of about 50 to 100 nm.

  As a method for forming the organic light emitting medium layer 22, a vacuum deposition method, a spin coating method, a spray coating method, a flexo method, a gravure method, a micro gravure method, an intaglio offset method, a printing method, an ink jet method, or the like is used depending on the material. Can do. When forming the polymer light emitting medium layer with a coating solution, it is preferable to control the vapor pressure, solid content ratio, viscosity, etc. of the solvent according to the forming method. Solvents include water, xylene, anisole, cyclohexanone, mesitylene, tetralin, cyclohexylbenzene, methyl benzoate, ethyl benzoate, toluene, ethanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, methanol, isopropyl alcohol, ethyl acetate, butyl acetate, etc. These may be a single solvent or a mixed solvent. In order to improve coatability, it is more preferable to mix an appropriate amount of additives such as surfactants, antioxidants, viscosity modifiers and ultraviolet absorbers as necessary. As a method for drying the coating solution, it is sufficient if the solvent is removed to such an extent that the electroluminescence characteristics are not hindered.

Next, the second electrode 23 (cathode layer) is formed by plasma film formation (FIG. 7). When the transparent electrode is formed as a cathode layer by sputtering or ion plating, the shielding portion described above is provided between the plasma generating portion 5 and the laminated substrate 2 so that the organic light emitting medium layer 22 is not damaged by plasma. 6 is provided.
As a material for the cathode layer, it is desirable to use a metal composite oxide such as ITO (indium tin composite oxide), indium zinc composite oxide, zinc aluminum composite oxide which is excellent in both transparency and resistivity.

  Further, in order to reduce the work function on the cathode side and increase the light emission efficiency, a substance having a high electron injection efficiency (electron injection layer) is preferably laminated on the interface between the organic light emitting medium layer 22 and the cathode layer. As the material for the electron injection layer, depending on the material of the organic light emitting medium layer, an alkali metal or alkaline earth metal having a low work function such as Li, Ca, Cs, Ba, an oxide compound, a fluoride compound, or nitridation of these metals. You may laminate | stack a compound. Further, these metal materials and metal compound materials may be used by doping the organic electron transport material in a small amount.

  The thickness of the electron injection layer needs to be in a range that does not hinder the light transmittance, is preferably about 0.1 to 50 nm, and more preferably 1 nm to 10 nm. . Moreover, there is no restriction | limiting in particular as a film thickness of a cathode layer, About 10 nm-1000 nm are preferable, Furthermore, about 100 nm is more preferable.

Finally, the substrate 20a and the substrate 20b are bonded together via the adhesive layer 24 (FIG. 8). The substrate 20b can be made of the same material as the base material 20a described above. Examples of the material of the adhesive layer 24 include a photo-curing adhesive resin, a thermosetting adhesive resin, a two-component curable adhesive resin, and an acid such as polyethylene and polypropylene. A thermoplastic adhesive resin made of a modified product or the like can be used as a single layer or laminated. In particular, it is preferable to use an epoxy thermosetting adhesive resin that is excellent in moisture resistance and water resistance and has little shrinkage during curing. Moreover, in order to remove moisture contained in the adhesive layer, a desiccant such as barium oxide or calcium oxide may be mixed. Depending on the material, the adhesive layer 24 may be formed directly on the substrate or by using a coating method such as roll coating, spin coating, screen printing method, spray coating, printing method or nozzle coating. Alternatively, it may be formed on another substrate in advance and laminated on the laminated substrate 2 or the substrate 20b in FIG. 7 using a transfer method or the like.

Example 1 and Comparative Examples 1, 2, and 3 based on the embodiment will be described with reference to FIGS.
<Example 1>
A glass substrate is used as the substrate 20a, and an ITO film is formed on the substrate 20a as a first electrode (anode layer) by a sputtering method, and then the ITO film is patterned by a photolithography method and a wet etching method (FIG. 5). ).
Next, a mixture (20 nm) of poly (3,4-ethylenedioxythiophene) and polystyrenesulfonic acid as the hole transport layer, and poly [2-methoxy-5- (2′-ethyl-hexyloxy) as the phosphor layer -1,4-phenylene vinylene] (MEHPPV) (100 nm) was formed by a spin coating method to form an organic light emitting medium layer 22 (FIG. 6).
Next, it is installed inside the organic electroluminescence manufacturing apparatus so that the surface 11 on the organic luminescent medium layer side of the laminated substrate 2 faces the target portion, and a 5 nm Ca film is formed as an electron injection layer, and the second electrode (cathode layer) ), An ITO film having a thickness of 100 nm was formed (FIG. 7).
Deposition of the ITO film as the second electrode will be described. As shown in FIG. 1, the substrate 1 was formed while transporting the laminated substrate 2. As the plasma film forming apparatus, a DC magnetron sputtering apparatus was used. A conductor 6a having an opening constituting the shielding part and a movable shielding plate 6b were used. As the conductor 6a having this opening, a conductor having a mesh-shaped opening inclined from an opening ratio of 5% to an opening ratio of 50% was used. As for the introduction gas, a supply port is installed on the laminated substrate 2 side from the conductor 6a having an opening, and argon gas and oxygen gas are introduced. Moreover, as a movable shielding plate, using a circular plate having a slit with a width of 10 mm that goes out from the center to the outer periphery, installed in a region where the aperture ratio of the conductor is 5-15%, while rotating at 30 rpm, As shown in FIGS. 1 and 2, the substrate was transported to form an ITO film. Finally, using an epoxy resin, a glass substrate was bonded as the substrate 20b to seal the organic electroluminescence element.
As a result of applying a voltage of 7 V to the produced organic electroluminescence element, light emission with a luminance of about 10000 cd / m ² can be confirmed from both the first electrode side (anode layer side) and the second electrode side (cathode layer side). It was. As a result of applying a voltage of 7 V to an organic electroluminescence element in which an Ag film was formed to a thickness of 100 nm without forming ITO as a cathode layer, the luminance was similarly about 10,000 cd / m ² from the first electrode (anode layer side). Thus, it was confirmed that there was no damage to the organic light emitting medium layer 22 due to the formation of the ITO film.

<Comparative Example 1>
In the manufacturing apparatus described in Example 1, an ITO film 100 nm was formed as the second electrode (cathode layer) without installing the conductor 6a having an opening and the movable shielding plate 6b.
As a result of applying a voltage of 7 V to the produced organic electroluminescence element, light emission with a luminance of 100 cd / m 2 was confirmed from both the first electrode side (anode layer side) and the second electrode side (cathode layer side). From this, it was found that by forming the ITO film, the organic light emitting medium layer 22 was damaged and the light emission efficiency was reduced to 1/100.

<Comparative Example 2>
In the manufacturing apparatus described in Example 1, an ITO film 100 nm was formed as the second electrode (cathode layer) without installing the movable shielding plate 6b. As a result of applying a voltage of 7 V to the produced organic electroluminescence element, light emission with a luminance of 2500 cd / m 2 was confirmed from both the first electrode side (anode layer side) and the second electrode side (cathode layer side). From this, it was found that by forming the ITO film, the organic light emitting medium layer 22 was damaged and the light emission efficiency was reduced to ¼.

<Comparative Example 3>
In the manufacturing apparatus described in Example 1, the ITO film 100 nm was formed as the second electrode (cathode layer) without installing the conductor 6 a having the opening. As a result of applying a voltage of 7 V to the produced organic electroluminescence element, light emission with a luminance of 1000 cd / m 2 was confirmed from both the first electrode side (anode layer side) and the second electrode (cathode layer side). From this, it was found that by forming the ITO film, the organic light emitting medium layer 22 was damaged and the light emission efficiency was reduced to 1/10.

It is a perspective view which shows an example of the organic electroluminescent element manufacturing apparatus of this invention. It is a perspective view which shows an example of the organic electroluminescent element manufacturing apparatus of this invention. It is a perspective view which shows an example of the organic electroluminescent element manufacturing apparatus of this invention. It is a perspective view which shows an example of the organic electroluminescent element manufacturing apparatus of this invention. It is sectional drawing which shows an example of the organic electroluminescent element of this invention. It is sectional drawing which shows an example of the organic electroluminescent element of this invention. It is sectional drawing which shows an example of the organic electroluminescent element of this invention. It is sectional drawing which shows an example of the organic electroluminescent element of this invention. It is the schematic which shows an example of the organic electroluminescent element manufacturing apparatus of this invention. It is the schematic which shows an example of the organic electroluminescent element manufacturing apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plasma film-forming apparatus 11 The surface of the laminated substrate by the side of the organic luminescent medium layer 12 The substrate surface of the laminated substrate 2 The laminated substrate 4 The target part 5 The plasma generating part 6 The shielding part 6a The conductor 6b having an opening The movable shielding plate 7 Gas supply Port 8 Protective plate 9 Magnet 10 Laminated substrate holding part 20a Substrate 20b Substrate 21 First electrode 22 Organic light emitting medium layer 23 Second electrode 24 Adhesive layer

Claims (6)

A method for producing an organic electroluminescent element, wherein a second electrode is formed by plasma film formation on a laminated substrate in which at least a first electrode and an organic light emitting medium layer are laminated ,
A shielding part is provided between the plasma generation part of the plasma film forming apparatus and the laminated substrate, the shielding part has an opening having an inclined opening ratio and has a ground potential, a slit, and a radius that is A movable shielding plate made of a disk larger than the major axis of the laminated substrate,
The method of manufacturing an organic electroluminescence element, wherein the plasma film forming step forms the film while rotating the movable shielding plate . A method for producing an organic electroluminescent element, wherein a second electrode is formed by plasma film formation on a laminated substrate in which at least a first electrode and an organic light emitting medium layer are laminated,
A shielding part is provided between the plasma generating part of the plasma film forming apparatus and the laminated substrate, and the shielding part has an opening and a conductor having a ground potential, and the movable having the opening having the same shape as the conductor. A shielding plate,
In the plasma film forming step, the aperture ratio is changed by sliding the conductor or the movable shielding plate. In the initial stage of film formation, the opening portion of the conductor is blocked by the movable shielding plate and the aperture ratio of the shielding portion is changed. The organic electroluminescence element manufacturing method is characterized in that the aperture ratio of the shielding portion is increased by combining the opening portion of the conductor and the opening portion of the movable shielding plate at a later stage of film formation. The method of manufacturing an organic electroluminescent element according to claim 1, wherein the movable shielding portion is made of stainless steel. In the organic electroluminescence element manufacturing apparatus in which the second electrode is formed by plasma film formation on a laminated substrate in which at least the first electrode and the organic light emitting medium layer are laminated, the plasma film formation apparatus for forming the plasma film includes: A target unit, a plasma generation unit, a holding unit for holding the laminated substrate, a shielding unit capable of changing the aperture ratio , an exhaust port, and a gas supply port ,
The shielding part includes a conductor having an opening with a sloped opening ratio and a ground potential, and a movable shielding plate made of a disk having a slit and a radius larger than the major axis of the laminated substrate,
The shielding part is provided between the plasma generation part and the holding part of the multilayer substrate ,
The exhaust port is disposed closer to the target portion than the conductor having the opening,
The gas supply port is disposed closer to the substrate than the conductor having an opening,
An apparatus for manufacturing an organic electroluminescence element, wherein the movable method of the movable shielding plate is a rotational movement . In the organic electroluminescence element manufacturing apparatus in which the second electrode is formed by plasma film formation on a laminated substrate in which at least the first electrode and the organic light emitting medium layer are laminated, the plasma film formation apparatus for forming the plasma film includes: A target unit, a plasma generation unit, a holding unit for holding the laminated substrate, a shielding unit capable of changing the aperture ratio, an exhaust port, and a gas supply port,
The shield includes an electric conductor having an opening and a ground potential, and the movable shielding plate having an opening having the same shape as the electric conductor,
The shielding part is provided between the plasma generation part and the holding part of the multilayer substrate,
The exhaust port is disposed closer to the target portion than the conductor having the opening,
The gas supply port is disposed closer to the substrate than the conductor having an opening,
An apparatus for manufacturing an organic electroluminescence element, wherein a movable system of the movable shielding plate is a slide.
6. The organic electroluminescence element manufacturing apparatus according to claim 4 , wherein the plasma film forming apparatus is a DC magnetron sputtering apparatus.

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